Placement devices are used for assembling components, e.g. components in hybrid microsystems, or for placing components on a substrate, e.g. a printed circuit board. Additionally placement devices may be used for other pick & place activities, such as taking components from a component supply belt and placing them on a location for further processing. In order to enable a fast manufacturing process, it is desired that the placement device places the components with a high speed. However, increasing the placement speed tends to increase the contact forces exerted by the gripper on the component or on the substrate. The current approach is to reduce these contact forces by moveably coupling the gripper to the other parts of placement device, wherein the gripper, that contacts the component, has a relatively low mass.
Such a placement device is described for example in U.S. 2005/0035613. The gripper described therein is mounted coaxially in a holder. A pretension is applied to the gripper by an electric or magnetic field. In this way the placing force is independent on the distance covered by the gripper relative to the holder when placing objects onto a substrate.
After the collision of the gripper and the component with the substrate, which causes the gripper to stop, the holder will in practice continue to move along a certain distance, e.g. some hundreds of μm before its movement stops. It has been recognized by the inventor that during this relative movement generally small lateral displacement occur in the guidance of the gripper. This may have various causes, e.g inaccuracies in the guidance system, a resilient suspension of the gripper in the holder that is not symmetrical, a deviation between the main axes of the guidance and the motion direction of the holder. These lateral displacements in the guidance of the gripper can lead to placement inaccuracies and/or stress build-up in the gripper.